Backpack



FIG. 1 is a perspective view of the backpack embodying my new design;

FIG. 2 is a front view of the backpack shown in FIG. 1;

FIG. 3 is a back view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines shown in FIGS. 1, 4, 5, and 6 are understood torepresent stitching.

The ornamental design for a backpack, as shown and described.